This invention relates to sun roofs for vehicles.
Vehicle sun roofs may comprise a plurality of relatively small movable closure panels as disclosed in U.S. Pat. No. 5,484,185 in which the panels are arranged side by side in a flat manner to cover the roof panel opening. To uncover the roof opening, beginning with the rearmost panel, each panel tilts its rear edge upward which is then unlocked from the panel ahead of it and moves rearward, until all panels have reached their most rearward position. When all panels have reached their final position, the panels are stacked parallel to each other, at an angled position mostly above the roof opening. Each panel is pivoted about a virtual axis positioned at a height above the roof panel opening. Since the panels lie next to each other and the clearance between panels should be minimized for visual purposes, this arrangement of the pivoting axes is necessary to avoid downward and forward movement of the front edge of the pivoting panel, to prevent a collision between the front edge of the currently pivoting panel and the panel forward of it, and the supporting components below it. With the pivoting axes located directly above the front edge of the panel, any forward and downward movement of the front edge during rotation can be eliminated.
Although the rotation axis is located above the front edge of the closure panel, the bearing structure has many shortcomings. The bearing structure of the pivot bearing and pivot bearing segment shape has a relatively large longitudinal dimension and is placed well in front of the panel edge. Since each panel is not always supported at its rear edge, the bearing segment must be large to support the weight of the panel. In the case of a multipanel roof, this can be acceptable due to the fact that there is an open space beneath the panel in front of the pivoting panel. In the case of a conventional single-panel sunroof, the space in front of the panel is typically occupied by many components such as the roof panel downward sealing flange, the stowed air deflector, the front frame and A-pillar drain holes/pipes, and cable guide pipes if the sunroof is driven from the front of the vehicle. Typically, there would not be any vertical support upon which the pivot bearing could rest. The functioning components typically need to be located within the outline of the movable panel for fitment of a conventional single-panel sunroof.
Many vehicle manufacturers have a strength requirement for an upward force pushing at the center of the closure panel, which would be then partially routed to the bearing structure. In this device, the pivot bearing shape is such that it would either need to be manufactured by a high performance resin injection or cast metal. In either case, an additional premium cost would be necessary over a general resin injection or stamped metal part, or combination of a stamping and injection part.
Furthermore, under the teachings of the prior art, the system can be simplified by component consolidation. In particular, the assembly of the plate carrier, the pivot bearing segment, and guide pin can be consolidated into one component for a conventional sunroof system.
A sunroof disclosed in U.S. Pat. No. 6,390,545 slides horizontally from a closed position in which it covers a vehicle roof panel opening, to a lowered uncovering position within a cavity disposed under the vehicle roof panel and above a vehicle headliner. In the closed covering position, the sunroof glass panel is able to rotate upwardly from the closed position to a pair of tilted positions for ventilation, and back down to the closed position to enable the panel to be slid to the lowered uncovering position. This sunroof's rotation producing components include a bracket, a driven shoe, a pivot pin, and a guide block for effecting sunroof rotation through the lowered, closed, and tilted positions. A joining process is needed to attach the pin to the bracket and the driven shoe and this pin becomes a rotation axis for the sunroof system. The guide block is typically fixed to a guide rail by a fastener or interference fit, which includes an open slot that will engage a fixed pin on the bracket. During operation, the bracket pin engages the guide block slot only in the lowered (uncovering), closed, and tilted positions. The force of a push/pull cable is transmitted through the bracket, the bracket pin, and the fixed guide block which allows rotation of the bracket and therefore the glass panel through the lowered, closed and tilted positions.
When the sunroof tilting rotation axis of the mechanism disclosed in U.S. Pat. No. 6,390,545 is positioned at a plane well below the roof panel opening, the radius length of the front and rear panel seal loci allows for a significant fore/aft component of movement, in relation to the roof panel opening. When a fixed guide block is used, there is also a fore/aft movement of the sunroof panel rotation axis with the movable front guide between the lowered, closed, and tilted positions that can be relatively large, particularly between the closed and lowered positions. This fore/aft movement can result in overcompression in the sunroof panel seal during sunroof rotation. Such overcompression may result in undesirable noises, such as a rubbing noise, or thumping noise when the friction of the overcompressed seal is overcome, and exits the roof panel opening when rotating from the closed position to the lowered position. The prior art shows a method to reduce this overcompression by raising the pivoting axis above the stationary guide rail. However, this type of countermeasure requires additional processes to create a pivoting axis by a joining pin or other bearing surface, and its height is therefore limited to the shape of the sunroof components, and the packaging space available around the bearing area.
A sunroof device disclosed in U.S. Pat. No. 6,817,658 slides from a closed covering position within a vehicle roof panel opening to a lowered, uncovering position that is located in a cavity under a vehicle roof panel and above a vehicle headliner. From the closed covering position, the sunroof glass panel is able to rotate upwardly to a tilted position for ventilation, or slide down to a lowered position for uncovering the roofs opening. This sunroof's rotation-producing components include a side plate, a front guide, and pivot pin. A joining process is needed to attach the pin to a side plate and a front guide and this pin becomes a rotation axis for the sunroof system. In this system, the front guide is fixed during rotation due to a locking feature. The system is locked while in the lowered (uncovering), closed and tilted positions. The force of a push/pull cable is transmitted through the side plate and fixed front guide which then allows rotation of the bracket and therefore the glass panel through the lowered, closed and tilted positions. As mentioned previously, when the sunroof's tilting rotation axis is positioned at a plane well below the roof panel opening, the radius length of the front and rear panel seal loci allows for a significant fore/aft component of movement, in relation to the roof panel opening.
U.S. Pat. No. 6,817,658 also discloses a method to reduce this overcompression by raising the pivoting axis above the stationary guide rail. However as mentioned above in connection with U.S. Pat. No. 6,390,545, this type of countermeasure requires additional processes to created a pivoting axis by a joining pin or other bearing surface, and it's height is therefore limited to the shape of the sunroof's components, and the packaging space available around the bearing area. Due to the nature of the fixed front guide during rotation of this sunroof device, the fore/aft movement of the sunroof rotation axis is eliminated.